Conventional RF and microwave long-distance communication systems are capable of receiving only signals whose field vectors E and B are nonzero, i.e., signals which carry real electromagnetic power as described by the Poynting vector. There are cases, however, where, for a particular antenna or another type of electromagnetic source, the field force vectors can be reduced to zero in parts or sectors of space (or even all space) while the components of the 4-vector potential (the magnetic vector potential A and the electric scalar potential Φ) are significantly different from zero.
The detection of the static magnetic vector potential A has been experimentally confirmed in quantum electrodynamics through the Aharonov-Bohm effect, as described by Y. Aharonov and D. Bohm, “Significance of the electromagnetic potentials in the quantum theory,” The Physical Review, vol. 115, No. 3, August 1959, pp. 485-491, which is hereby incorporated by reference in its entirety, in systems involving an electron beam passing through a double-slit with a magnetized hair-thin ferromagnetic filament in-between the slits. A shift in the electron interference pattern is observed with the filament in and out of the double-slit arrangement, as described in R. G. Chambers, “Shift of an electron interference pattern by enclosed magnetic flux,” Physical Review Letters, vol. 5, No. 1, July 1960, pp. 3-5, which is hereby incorporated by reference in its entirety. There is a substantial body of literature dedicated to the detection of the magnetic vector potential A due to magnetostatic sources (coils, toroids, magnetized ferromagnetic cores, etc.) in regions of space where the magnetic field vector B is zero, see, for example, M. Peshkin and A. Tonomura, The Aharonov-Bohm Effect, Lecture Notes in Physics, vol. 340, Springer-Verlag, Berlin, 1989, which is hereby incorporated by reference in its entirety. Similarly, electrostatic arrangements have been investigated where the effect of the scalar potential Φ is measurable in regions where the electric field vector E is zero, see Y. Aharonov and D. Bohm, “Significance of the electromagnetic potentials in the quantum theory,” and M. Peshkin and A. Tonomura, The Aharonov-Bohm Effect. In all cases, the effect is quantum or microscopic in the sense that it is observed through electron beam interference. To date, there are no successful A-detection experiments in the classical macroscopic sense involving time-varying signals, e.g., radio-frequency or microwave signals. A theoretical analysis of the time-dependent Aharonov-Bohm effect is presented in B. Lee, E. Yin, T. K. Gustafson, and R. Chiao, “Analysis of Aharonov-Bohm effect due to time-dependent vector potentials,” Physical Review A, vol. 45, No. 7, April 1992, pp. 4319-4325, which is hereby incorporated by reference in its entirety, for the case of optical frequencies and a possible experimental setup is outlined, which is based again on electron beam interference. However, there is no published data on the realization of this optical experiment. To date, there is no known technology reported in the scientific and engineering literature, which can unambiguously prove that the coupled electrodynamic potentials A and Φ (often referred to as the 4-vector potential) have any physical significance, i.e., that they are measurable. This holds for both microscopic observations such as electron interference patterns as well as macroscopic observations such as the measurements of voltage, current or power signals.
The detection of static curl-free magnetic vector potential A, i.e., curlA=0, where the magnetic field vector B is zero since B=curlA, has already been considered in practical systems discussed in U.S. Pat. No. 4,432,098 to Gelinas and U.S. Pat. No. 4,491,795 to Gelinas, which are both hereby incorporated by reference in their entirety. The detection devices utilize a single Josephson junction (U.S. Pat. No. 4,432,098) and a quantum interferometer (U.S. Pat. No. 4,491,795) consisting of two Josephson junctions. The latter belongs to a group of devices commonly referred to as superconducting quantum interference devices (SQUIDs). The way Josephson junctions, as described in B. D. Josephson, “Coupled superconductors,” Review of Modern Physics, vol. 36, January 1964, pp. 216-220, which is hereby incorporated by reference in its entirety, and SQUIDs respond to the magnetic vector potential A is well understood, see, for example, M. Tinkham, Introduction to Superconductivity, 2nd ed., Mc-Graw-Hill, 1996, Chapters 6 and 7, which is hereby incorporated by reference in its entirety. Their major drawback is that they require a cryogenic environment in order to achieve the superconducting state. In U.S. Pat. No. 4,432,098, transfer of information utilizing such signals is also proposed, but no practical communication system for implementing such a transfer is disclosed.
Further, U.S. Pat. No. 5,845,220 to Puthoff, which is hereby incorporated by reference in its entirety, describes communicating through time-varying ‘pure potential’ (zero-field) signals where the receiver is again a Josephson junction. Here, the junction is placed within an electromagnetic shield in addition to the required cryogenic chamber. The electromagnetic shield supposedly is pervious to the pure-potential signals while eliminating interference from conventional (E,B) signals. The proposed system uses a transmission device, which is quasi-static in nature, and whose signals are to be detected in the device's near zone, which severely limits the distance over which the signals can be detected. Moreover, the device generates a vector potential A, whose polarization is orthogonal to the direction of the signal's propagation. Such a design principle leads to a substantial conventional (E,B) signal in the far zone compared to the pure-potential signal, thereby inevitably leading to substantial power consumption and, possibly, interference.